Generator/Motor Synchronising

Article lead image — Zion Power Station - a decommissioned nuclear power plant close to Chicago, USA. In order to use the two 800MW generators as synchronous condensers the steam turbines were disconnected and an SSS Clutch added to each generator allowing a mobile motor/torque converter package to be coupled to the machine to drive the generator up to synchronous speed.

SSS Clutches can be used to engage/disengage auxiliary drives to run generators or large motors up to speed so that they can be connected to the grid.

Synchronising packages with SSS Clutches are used both for synchronous machines, which need accurate synchronisation, and large induction motors, where the "in rush" current of starting a motor direct-on-line would be unacceptable.

SSS Clutches can…

Be "stand alone" with a casing to allow one starter motor to be used to start multiple machines.
Incorporate a thrust bearing to position the generator rotor after it has been disconnected from the axial bearing in the turbine.
Incorporate a turning gear.